Telephone-exchange system.



L. H. JOHNSON.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED MAILZh I917.

Patented Oct. 8, 1918.

STATE-S PATENT F BrooMrIEI ip, NEW JERSEY, Assrenon r own srniti\i=itrlnefitro tRATED, OF NEW YORK, N. Y., A ooRroRATIoN-or NEW 52031:.

"*rErErnonE-Excrrmens stem.

"Specification of Letters'rateiit.

retestweeteners,

Application filed Mardh21,*l917i seriarnc-radesc.

LEWIS H. i J OHNSON,

l States, residin at y of-Essex and tate uvented certainnew its in Telephone-Exch the following is a exact description.

es to telephone eX- e'ct being the proviing means for such object of this'inventhe nuinber of conuit'of-a ring'ing sys- LS four-party selece'code.ringing in g button 'for g each of inc, the actuation of j is; character of ring- ,he line, to simplify .rcuits in whichsuch loyed; and I to so orf such ringing sys- .seaof anyadditional a station on a magie may be manually trated in the accomiich there is shown )hone exchange syspropenunderstandv In the drawin :uit C connected with e A, and telephone mer 'of the common 5 tter of the magneto my line B there are E, F,'G and -H. At ,ll bells jare connectdeof thev line and rF and the call veen the tip side of He at th I s en of call bell is bridged hr'oughfa back con- )rd circuit is a ring.- ising lour -buttons :ssion of any one of wn contacts shown sure, The contacts 1 inclosure are only ot the line and through the call bellfat staoperated when any one of :the plu-ngers {56f the ringing-key st*1'-uet'ure-is in its way down position, while the contacts associated :with each plunger are actuated when the 1 respective plungers are either in the way-down or an intermittent lOCklIigjP'OSltlOn. Associated "with the ringing key structure are a plurality of relays which control 'the I application of ringing current to the called line either over the ring or tip side thereof. Ringing current issupplied from generator :5'through,interrupters(3 and -7. ,These two rinterrupters,-as well -as the third interrupter-S, areon the saine'shaft, whichhnakes one revolution every six seconds, In this -manner, when interrupter 6 isconnected in circuit with generator 5 and the dine, there is provided ringing interval of twosec- "ends, ;followcdby-a silent interval of four I seconds, while if interrupter 7 be connected in circuit with generator '5 and the line,

there I is provided a ringing interval of one second, followed by a sllent-interival of one second, a ring ng interval of one-second,

ofthreeseconds. I I g Assuming that'the operator has been requested to make connection withstation E on line B, the insertion of the plug into; the

the call bell at station :is connectedi-be-i tween the-ring sideof the line and, ground,

of the ringing key structure. will depressed into its lockingfposition, whereupon relay 12 is operated over a circuit from battery, through the winding of relay 12,

contact of plunger 1, normal contact ofrelay 13, normal contact of trippingrelay {let and the contact of aelay lfi to ground,

The call bell-at stationEis therefore, opertion E 'to ground. 7 The'subseriberat station E,re sponding, causes the operation of relay lh whereupon relay 13 operates andv which istheirfollowed by asilent interval .jackof line B'c'ausesthe -operation of marandiisthe first party on the line, ,plunger 1 i .LnWrs H Jo Nsmto: ooivrrAn mcoaro To all whomc't'may 0on0 Be it knownthat 1, a citizenof the Unitec' Bloomfield, in the count of New Jersey, have i] rand useful 'Improvemen change Systems, ofwwhi full, clear,1concise, and This invention relat change systems, its obj sion of improved ring systems.

More specifically, the

'tion is the reduction I of tacts in the vringing circ tem commonly known '2 tive or senn-selectw which 1 there is a :ringing the four stations on-alf a :button 1 determining tl ing current sent over t the wiring of the linkci ringing systems are em ganize the apparatus 0 tems, that withoubthe u apparatus a subscriber: neto 'or local battery :lil signaled.

This invention =is'illus .panying "drawing in :w]

only so much of 'a 'tele tem a se is necessary for a ing oii this "invention.

there is shown a-linkcirc a calling telephone 1in lines B "and D,, the for: battery type "and the la or local battery type.

To the common batte connected four stations stations E and Gtheea red between the ring si ground, and at stations bells are connected bett the line and ground wh the magneto line :D the across the line circuit t tact of the -switchhook.

Associated-with the (N -ing key :strueture compr 1, 2, 3 and l-the depre :which controls way-do within the dotted :inclo shown within the dotte locks up, thereby short-circuit-ing relay 12,

which releases, removing the ringingcurrent from the line, and completing the talking strands of the cord circuit.

Should station F have been desired, plunger 2, instead of 1, would have been depressed, causing the operation of relay 16 over a circuit from battery through the Winding of relay 16, the alternate contact of plunger 2, normal contacts of relays 13 and let and the contact of relay 10 to ground.

The operation of relay 16 closes a contact in circuit with relay 17. Relay 17 operates when: interrupter 8 has rotated, so that the brush is in contact with the segment to which battery is connected, the operating circuit'for pick-up relay 17 being from battery through the line segment and brush or interrupter 8,

normal contact and winding of relay 17 and left-hand alternate contact of relay 16 to ground. Relay 17, in operating, completes a locking circuit for itself through its righthand alternate contact, and causes the operation oi" relay 12 over a circuit from battery through the winding of relay 12, lefthand alternate contact of relay 1.7, normal contacts of relays 13 and 14 and the contact of relay 10 to ground. The call bell at station F is operated by current from generator '5 through interrupter 6 overthe tip side of the line.

If station G had been desired, plunger 3 "would have been depressed, causing the operation of relay 15 over a circuit from bat- .tery through the winding of relay 15, alternate contact of plunger 3, normal contact of plunger 2, normal contacts of relays 13 and 14c, and the contact of relay 10 to ground. Relay 15, in operating, shifts the ringing circuit from interrupter 6 to interrupter 7 and following the operation of relay 15,

when the brush of interrupter 8 has come in contact with the line segment to which battery is connected, pick-up relay 17 operates and locks-up as hereinbefore described, the

ground for this relay being supplied through the right-hand alternate contact of relay 15, instead of through the left-hand alternate contact of relay 16, as was the case when plunger 2 was depressed. Following the operation of relay 17, relay 12 operates.- The call bell at'station G isthereupon operated by current from generator 5 supplied Y through interrupter 7 over the ring side of y the line.

. Should station H have been desired, plunger a would have been depressed, whereupon *relay 15 wouldoperate over a circuit from battery through the winding of relay 15, left-hand alternate contact of plunger 1, nor- "mal contacts of plungers 3 and 2, normal contacts of relays 13 and 14: and the contact of relay 10 to ground. Relay 16 is also op- }erated atthis time, the circuit therefor being from battery through the Winding of relay 16, right-hand alternate contact of plunger 1, normal contacts or plungers 3 and 2, normal contacts of relays 13 and 1 1 and the contact of relay 10 to ground. The call bell atstation H is thereupon operated by current from generator 5, through interrupter 7 over the tip side of the line.

. Should connection have been desired with the magneto line D, the insertion of the plug into the jack of that line would cause the operation of cut-off relay 20 associated therewith. Relay 10 does not operate, however, for it is marginal and does not operate when connected in series with the cut-off relay of the magneto line which is of high resistance. The resistance of the cut-oil relays of common battery lines is low, so.

that when relay 10 is connected in circuit with a cut-01f relay of a common battery line, it operates. To apply ringing current to a magneto telephone line for the purpose 01 causing the operation of the call bell of the station on that line, the first plunger or button No.1 of the ringing-key structure is depressed, thereby causing the operation of relay 12 over a circuit from battery through the winding of relay 12, contact of plunger 1, normal contacts of plungers 2, 3 and 4, and the upper alternate way-down contact of the ringing key. The call bell at the station on the magneto line, which is connectc d-across the line, is thereupon operated by current from grounded generator 5 through the lower alternate way-down contact of the ringing key, right-hand normal contact of relay-l6, lower alernate contact of relay 12, ring contacts of the plug and ack, over one side of line D, through the call bell at the station thereon, back over the other side of the line, tip contacts of the jack and plug, upper alternate contact of relay 12 and lefthand normal contact of relay 1-6 to ground.

The interrupter 6 and generator 5 may be considered as a source of ringing current of one character, while interrupter 7 and generator 5 may be considered as a source of ringing current ofanother character. For all intents and purposes, so far as this invention is concerned, there may be separate generators producing currents of difi'erent frequencies. It will beunderstood that the I relay 15 determines which source of current projected.

selected source is to be projected, and a ringing relay controlled by the key for connecting the selected source to the line.

2. A telephone exchange system comprising a telephone line, a link circuit connected therewith, sources of distinctive ringing current, a ringing key in the link circuit, means controlled by the key for selecting the source of ringing current to be connected with the line, means controlled by the key for determining the side of the line over which current from the selected source is to be projected, and means controlled by the key for connecting the selected source to the line.

3. A telephone exchange system comprising a telephone line, a link circuit connected therewith, sources of distinctive ringing current, an operator-controlled ringing key in the link circuit, a relay controlled by the key for selecting the source of ringing current to be connected with the line, a relay controlled by the key for determining the side of the line over which current from the selected source is to be projected, and a ringing relay controlled by the key and cooperating with the selecting and determining relays for connecting the selected source to the line.

4:. A telephone exchange system comprising a telephone line, a link circuit, a relay in the link circuit operating upon connection thereof with the line, an operator-controlled ringing key in the link circuit, sources of distinctive ringing current, a relay for selecting the source of ringing current to be connected with the line, a relay for determining the side of the line over which cur- Copies of this patent may be obtained for rent from the selected source is to be projected, both the selecting and determining relays being jointly controlled by the ringing key and by the first-mentioned relay, and a ringing relay controlled by the determining relay and cooperating with the selecting and determining relays for connecting the selected source to the line. 7

5. A telephone exchange system comprising a connnon battery telephone line, a plu rality of signal responsive devices connected therewith, a magneto telephone line having a signal responsive device connected thereto, a link circuit for connecting with either the 5 common battery or the magneto line, sources of distinctive ringing current, a ringing key equipped with a plurality of ringing buttons, one corresponding to each of the signaling devices connected with the common battery line, means controlled by the ringing key for selecting the source of ringing current to be connected with the common battery line, a relay in the link circuit operating upon connection of the link circuit with the common battery line to render the selecting means effective but not operating when the link circuit is connected with the magneto line whereby the selecting means is rendered non-effective, and'a relay controlled by one of the buttons of the ringing key to connect current from one of the sources to a magneto line.

In witness whereof, I hereunto subscribe my name this 20th day of March, A. D. 1917.

LEWIS H. JOHNSON.

five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

